Prior art pile guides comprise square structures mounted on the floating dock and surrounding the opening through which the pile protrudes. These prior guides are rectangular, but usually square structures having four pile engaging, horizontal rollers extending outwardly above the top surface of the dock. One or more of these rollers engage the pile as a dock moves vertically. Such prior art pile guides are designed for different size piles from about 10 inches in effective diameter. Each different sized pile has its own pile guide, with a dimension of the pile guide generally conforming to the size of the pile. Consequently, the guide manufacturer must supply different pile guides to installers of floating docks so the guides can accommodate the particular size of piles being used with the particular dock.